Data Dictionary
of
Multi-functional Smart Lampposts
Positioning Devices
Version 1.02
August 2019
© The Government of the Hong Kong Special Administrative Region
The contents of this document remain the property of, and may not be reproduced in whole or in part
without the express permission of the Government of the HKSAR
Version Details of Change Effective Date
1.0 Initial Release.
28 June, 2019
1.01 Minor update 23 July, 2019
1.02 Minor update 28 August, 2019
Data Dictionary of Multi-functional Smart Lampposts Positioning Devices (Version 1.02) P.1 Lands Department
Introduction
Development of Multi-functional Smart Lampposts aimed to support the Hong Kong Smart City development. Lands Department (LandsD) is
responsible for provision of positioning services to public. The positioning devices of LandsD on Smart Lampposts include Bluetooth beacons,
RFID tags, and Geo-QR codes. Developers can use this information to develop positioning related applications.
1. Bluetooth Beacons
The Bluetooth beacon transmits 2.4 GHz Bluetooth Low Energy (BLE) signals containing unique beacon identifier (ID) for real-time positioning
applications with about 5m positioning accuracy for general smartphone (both iOS and Android) users. For each lamppost, 2 Bluetooth Beacons
are installed at about 4m above ground and 2 others are installed at about 2m above ground.
2. RFID Tag
The RFID tag pack consists of 3 passive Ultra-High Frequency (UHF) RFID Tags. They are installed evenly along circumference of each lamppost
base and at height of 0.1m above ground.
The passive RFID tag stores the corresponding lamppost number
and relevant location information. The information can be
retrieved by common commercial RFID readers remotely at range
up to 10 m for various location-based applications, especially for
navigation application for visually impaired persons.
3. Geo-QR Codes
3.1 Geo-QR Code Tags
The Geo-QR code tag consists of a passive Near Field
Communication (NFC) tag readable by smartphones (both iOS and
Andorid) and one Quick Response Code (Geo-QR Code) printed on
Image 1 - Geo-QR Code Tag (Sample) Image 2 - Geo-marker (Sample –
not to scale)
Data Dictionary of Multi-functional Smart Lampposts Positioning Devices (Version 1.02) P.2 Lands Department
the cover panel of the tag (Image 1). It is installed at about 1.3m above ground, facing towards pedestrian walkway.
The Geo-QR code provides accurate positioning information and a platform to access nearby geographical information. The passive NFC tag
provides users with high security positioning data and lamppost information for various location-based applications, such as accident and
emergency reporting.
3.2 Geo-marker
The Geo-marker is a 150mm x 300mm aluminum plate consists of one Geo-QR code and one Target Marker (Image 2) mounted at about 3m
above ground facing carriageway. The Geo-marker provides accurate positioning information for various location-based applications.
The Geo-QR code provides accurate positioning information for various location-based applications, and also work as a unique visual identifier
for the Target Marker annexed. The Target Marker can provide precise coordinates for supporting various smart city applications, such as
creation and maintenance of high-quality 3D digital maps, production of geo-referenced street view video, road inventory asset management
and etc.
Data Dictionary of Multi-functional Smart Lampposts Positioning Devices (Version 1.02) P.3 Lands Department
Datasets
Six datasets are provided for different positioning devices mounted on Multi-functional Smart Lampposts in JSON format.
Dataset Information
Smart Lamppost (LP): Positioning information of the Smart Lamppost
Unique ID: LP_NUM
Bluetooth Beacon (iBeacon) (IB): Broadcast information of the Bluetooth beacon (iBeacon)
Unique ID: “BLE_IB_MAJOR” + “BLE_IB_MINOR”
Bluetooth Beacon (Eddystone) (EDS): Broadcast information of the Bluetooth beacon (Eddystone)
Unique ID: BLE_EDS_INSTANT
Geo-QR Code Tag (NFC): Positioning information of the Geo-QR code tag (NFC and Geo-QR code)
Unique ID: LP_NUM
RFID Tag (RFID): Positioning information of the RFID tag
Unique ID: RFID_TID
Geo-marker (GM): Positioning information of the Geo-marker
Unique ID: GM_ID
Data Dictionary of Multi-functional Smart Lampposts Positioning Devices (Version 1.02) P.4 Lands Department
Application Programming Interface (API) service
The API provides the datasets for different positioning devices mounted on Multi-functional Smart Lampposts.
Using GET request:
https://www.geodetic.gov.hk/lpapi/?<variables>=<values>
Example Requests:
Get information of specific type of positioning device
Example 1: Get Smart Lamppost information
https://www.geodetic.gov.hk/lpapi/?db=lp
Example 2: Get information of all positioning devices
https://www.geodetic.gov.hk/lpapi/?db=all
Get information according to specific conditions (e.g. Lamppost Number or Search Area)
Example 3: Select by Lamppost Number
https://www.geodetic.gov.hk/lpapi/?db=all&lp=DF3633 or
https://www.geodetic.gov.hk/lpapi/?db=nfc&lp=DF3633
Example 4: Select by defined search area (HK1980 Grid coordinates)
https://www.geodetic.gov.hk/lpapi/?db=all&n=825000&e=825000&bufn=100&bufe=100
Example 5: Select by defined search area (WGS84 Geographical coordinates)
https://www.geodetic.gov.hk/lpapi/?db=all&lat=22.2&long=114.12&buflat=100&buflong=100
Data Dictionary of Multi-functional Smart Lampposts Positioning Devices (Version 1.02) P.5 Lands Department
Variables:
Variables
(Case
insensitive)
Description Remarks
db Database Mandatory variable
Valid values (case insensitive):
LP (Smart Lamppost)
IB (Bluetooth Beacon - iBeacon)
EDS (Bluetooth Beacon - Eddystone)
NFC (Geo-QR Code Tag)
RFID (RFID Tag)
GM (Geo-marker)
ALL (All positioning devices)
lp Lamppost number Lamppost number assigned by Highways Department
Example: DF3633
n Northing (HK1980 Grid coordinates) Northing coordinate of the centre point of the search area
Unit: metre
e Easting (HK1980 Grid coordinates) Easting coordinate of the centre point of the search area
Unit: metre
Data Dictionary of Multi-functional Smart Lampposts Positioning Devices (Version 1.02) P.6 Lands Department
bufn Buffer in north-south direction Buffer from the centre point in north-south direction
Unit: metre
bufe Buffer in east-west direction Buffer from the centre point in east-west direction
Unit: metre
lat Latitude Latitude of the centre point of the search area
long Longitude Longitude of the centre point of the search area
Data Dictionary of Multi-functional Smart Lampposts Positioning Devices (Version 1.02) P.7 Lands Department
buflat Buffer in north-south direction Buffer from the centre point in north-south direction
Unit: metre
buflong Buffer in east-west direction Buffer from the centre point in east-west direction
Unit: metre
Data Dictionary of Multi-functional Smart Lampposts Positioning Devices (Version 1.02) P.8 Lands Department
Datasets:
Dataset
Field Description Allow
Null Remarks
LP IB EDS GM NFC RFID
LP_NUM Lamppost number NO String
LP_NORTH
Northing coordinates (HK1980 Grid) of lamppost NO Numeric
Round to the nearest 0.1 m
LP_EAST
Easting coordinates (HK1980 Grid) of lamppost NO Numeric
Round to the nearest 0.1 m
LP_GL
Ground level of lamppost above Hong Kong
Principal Datum (HKPD)
NO Numeric
Round to the nearest 0.1 m
LP_LAT
Latitude (Decimal Degree) of lamppost in WGS84
(Reference Frame: ITRF96 (1998:121))
NO Numeric
Round to the nearest 0.000001 degree
LP_LONG
Longitude (Decimal Degree) of lamppost in WGS84
(Reference Frame: ITRF96 (1998:121))
NO Numeric
Round to the nearest 0.000001 degree
BLE_IB_UUID
UUID of Bluetooth beacon (iBeacon) NO 32 hexadecimal digits split into 5 groups
e.g.B19AF0047F2A49728F3937D26C29
CB9E
BLE_IB_MAJOR
Major value of Bluetooth beacon (iBeacon)
YES Numeric
5 unsigned integer values (0-65535)
BLE_IB_MINOR
Minor value of Bluetooth beacon (iBeacon)
YES Numeric
5 unsigned integer values (0-65535)
BLE _IB_TX
Transmission power (Tx power) in dBm unit of
Bluetooth beacon (iBeacon)
YES Signed integer
e.g. -20
BLE_IB_HGT
Location of Bluetooth beacon above ground
U = Upper, L = Lower
YES String (U / L)
Data Dictionary of Multi-functional Smart Lampposts Positioning Devices (Version 1.02) P.9 Lands Department
Dataset
Field Description Allow
Null Remarks
LP IB EDS GM NFC RFID
BLE_EDS_NAMESPACE
Namespace of Bluetooth beacon (Eddystone) YES 20 hexadecimal digits
e.g. B19AF00437D26C29CB9E
BLE_EDS_INSTANT Instant ID of Bluetooth beacon (Eddystone) YES 12 hexadecimal digits
BLE_EDS_TX
Transmission power (Tx power) of Bluetooth
beacons in dBm unit (Eddystone)
YES Signed Integer
e.g. -20
BLE_EDS_HGT
Location of Bluetooth beacon above ground
U = Upper, L = Lower
YES String (U / L)
RFID_TID Transponder ID of RFID tag YES String
RFID _EPC Electronic Product Code of RFID tag YES String
NFC_URL
URL of Geo-QR code tag NO URL
e.g.
https://www.geodetic.gov.hk/LP/?LP=
42373
NFC_GEOURI
Uniform Resource Identifier for
Geographic Locations of lamppost (IETF RFC
5870)
NO String
e.g. geo:22.280713,114.173925
NFC_LP
Lamppost number (for Geo-QR code tag) NO String
e.g. LP:42373
NFC_HK80
HK1980 grid coordinates of lamppost
(for Geo-QR code tag)
NO String
e.g. HK80:824584.0N,829798.0E,2.1H
NFC_UID
NFC UID NO String
e.g. UID:04F94A0AAA5280
NFC_LOC
Location code (Reserved) NO String
e.g. LOC:
Data Dictionary of Multi-functional Smart Lampposts Positioning Devices (Version 1.02) P.10 Lands Department
Dataset
Field Description Allow
Null Remarks
LP IB EDS GM NFC RFID
NFC_TIME
Last modified time of Geo-QR code tag content NO String
e.g. TIME: 2019-05-22
NFC_VER
Version of Geo-QR code tag content format NO String
e.g. VER:1.0
NFC_SHA256
SHA256 hash of the Geo-QR code tag content NO String
e.g.
SHA256:7BB3941803DD68F60DB0EA
51A45A39959489DBA0984BD787E38
988514062B83B
GM_NORTH
Northing coordinates (HK1980 Grid) of Geo-marker YES Numeric
Round to the nearest 0.01 m
GM_EAST
Easting coordinates (HK1980 Grid) of Geo-marker YES Numeric
Round to the nearest 0.01 m
GM_ID
Unique ID for Geo-marker: LP no. + GM1A/B YES String
e.g. AB1234GM1A
GM_HGT
Height value of Geo-marker above Hong Kong
Principal Datum (HKPD)
YES Numeric
Round to the nearest 0.01 m
GM_URL
URL of Geo-marker YES URL
e.g.
https://www.geodetic.gov.hk/LP/?LP=
42373#GM1A
GM2_HGT (Reserved) YES